The present invention relates to improvements in a door latch and more particularly to an improved locking latch mechanism for positively securing roll-up doors such as used on trailer-tractor vehicles or the like so that the door is automatically latched with its closing and can only be opened by activating an unobvious release member.
Trailor-tractor roll-up doors are commonly latched in a closed position, by manually operated locking mechanism which are readily accessible from the ground. For security to prevent unauthorized opening, the release handle is manually pivoted to a latching position after the door is closed and most often secured with a padlock. In the absence of the driver, the padlock or exposed locking mechanism can be broken, the door opened and the contents tampered with or stolen. Security of the roll-up door is imparative to protect valuable contents of a truck or trailer. As an example of the lack of security offered by conventional padlocking, insurance companies have found that a padlocked roll-up door can be broken and the contents stolen within a very short time, even while a truck is waiting for a traffic light.
While the features of the invention, as will be described herein, are particularly well suited for use on trucks or tractor-trailer type vehicles, it will be appreciated by those skilled in the art that the features of this invention may be employed for securely locking various other roll-up doors as well.